Multifunctional rainfed margins for a better carbon and biodiversity balance

Abstract

Multifunctional margins (MFM) are strips of spontaneous or sown vegetation that are implanted in agricultural plots performing multiple functions. Their establishment in rainfed arable crops is an innovative agricultural practice and a source of multiple environmental and agronomic benefits. They serve as shelter for wildlife, favour the presence of pollinators and auxiliary insects and represent a physical barrier to runoff and drift of phytosanitary products. Once the margins are mowed, the organic residues are degraded by the soil biota, causing a recirculation of nutrients and an increase in organic matter. In this work, the effects of MFM on biodiversity of epigean fauna and the carbon sequestration in soil were studied. Three types of margins were compared: two different sown mixtures and spontaneous flora as control; likewise, the adjacent crop was tested. The margins promoted greater arthropod biodiversity than the crop, especially beetles. The soil analysis showed a loss of carbon in the crop conventionally managed, increasing in all types of MFM either sown as spontaneous ones. This practice has great potential of implementation in any type of extensive crop.